In billiards, if no torque is supplied, when the moving cue ball strikes a stationary ball the two balls often move off at right angles after the collision. The best explanation for this is that

A) the collision is elastic and kinetic energy must be conserved.
B) the collision is inelastic and kinetic energy must be conserved.
C) the collision is elastic and potential energy must be conserved.
D) the collision is inelastic and potential energy must be conserved.

Amass has an acceleration of 10- 2t. what is its velocity and displacement if it started at x- 4m and the initial velocity was 8m/s? at what time does it have 0 velocity? graph all graphs.

Imagine you are riding on a yacht in the ocean and traveling at 20 mph. you then hit a golf ball at 100 mph from the deck of the yacht. you see the ball move away from you at 100mph, while a person standing on a near by beach would observe your golf ball traveling at 120 mph (20 mph + 100 mph). now imagine you are aboard the hermes spacecraft traveling at 0.1c (1/10 the speed of light) past mars and shine a laser from the front of the ship. you would see the light traveling at c (the speed of light) away from your ship. according to einstein’s special relativity, how fast will a person on mars observe the light to be traveling? a) 0.1c (1/10 the speed of light) b) c (the speed of light) c)1.1c (c+0.1c)

Achlorine atom has 17 protons and 18 neutrons. what is its mass number? what is its atomic number?